Hi my laser driver works wrong way around M03s256 laser of m03s0 laser is on m03s250 laser low power. Got spare arduino nano maybe use to change laser output around know must edit gcode laserweb3 arduino uno cnc shield grbl 1.1f M03s0 measured 0.2v M03s256 measured 4.9v over spindle pins
This is the correct way like it should work. Higher S-value should produce higher voltage on the output pin. If you are using a CO2 laser PSU, they need to pull down the L pin to fire. You can use an NPN Transistor or N-Channel Mosfet to reach that.
